The proposed study is a response to the expansion of a study of 2-chloro-2-deoxyadenosine (2-CdA) to a multicenter trial. In this study, eligible patients with severe rhematoid arthritis will be treated with a weekly oral dose of 2-CdA for 12 weeks followed by monthly treatments for 6 months and 3 months of follow-up off of therapy. Disease activity will be monitored using a variety of parameters during the year of therapy and follow-up. Lymphocyte and monocyte counts will be followed to ensure depletion of these cell types in response to 2-CdA.